Thermostat displays E18 and the app reports ‘Heat pump integration error’; external heat pump data is unavailable.
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety: Turn off power to both the heat pump and Ngenic control module before touching any wiring.
- Check interface wiring: Verify that the Modbus/serial wires are connected to the correct terminals on both the heat pump and Ngenic integration port, with correct polarity.
- Confirm power to gateway: Ensure any external Ngenic heat pump gateway module has power and status LEDs are normal.
- Verify protocol settings: In the Ngenic app or installer menu, confirm the correct heat pump model, Modbus address, and baud rate are configured.
- Restart both systems: Power-cycle the heat pump and Ngenic control module to re-establish communication.
If E18 persists, consult Ngenic documentation for supported heat pump models; an incompatible firmware or gateway may need updating or replacing.
Repair Difficulty
Required Part
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